アントラキノンアゾール系建染メ染料の研究(第1報)

アントラキノンオキサゾール環の共役効果

抄録

1-Anilinoanthraquinones (2_a-2_c) having anthraquinone-oxazole ring in paraposition were synthesized, visible absorption spectra of these were compared with 1-anilino- and 1-(4-R-substituted-anilino)anthraquinones (R=NH₂ or NO₂), and clarified that anthraquinone-oxazole ring had electron-attractive property and its intesity was in order of nitro ≥ anthraquinone (2 : 1) oxazole > anthraquinone (1 : 2) oxazole a> anthraquinone (2 : 3) oxazole. These three kinds of dye (2_a-2_c) were synthesized by Ullmann condensation of 1-aminoanthraquinone and corresponding 2-(4-bromophenyl) anthraquinoneoxazole (3_a-3_c), respectively. 2-(4-Bromophenyl) anthraquinone-oxazoles (3_a-3_c) were synthesized as follows: (1). 2-Amino-3-hydroxyanthraquinone or2-amino-3-bromoanthraquinone was benzoylated with 4-bromobenzoyl chloride and each was treated for oxazole ring formation to obtain the same 2-(4-br.omophenyl) anthraquinone (2 : 3) oxazole (3_a). (2). Similarly, the reaction of 1-amino-2-hydroxyanthraquinone and 4-bromobenzoyl chloride caused benzoylation and oxazole ring formation at the same time and gave 2-(4-bromophenyl) anthraquinone (1 : 2) oxazole (3_b). This extraordinary reactive property was explained by intramolecular hydrogen bonding. Also, (3_b) was obtainable by benzoylation of 1-amino-2-bromoanthraquinone with 4-bromobenzoyl chloride and its oxazole ring formation but the yield was low. (3). Benzoylation of 1-hydroxy-2-aminoanthraquinone with 4-bromobenzoyl chloride and its oxazole ring formation gave 2-(4-bromophenyl) anthraquinone (2 : 1)-oxazole (3_c). The dyes (2_a-2_c), synthesized by condensation of 2-(4-bromophenyl) anthraquinone-oxazoles and 1-aminoanthraquinone, were used for dyeing of cotton by 2% IW method and following results were obtained on vat dyeing, color, and light fastness: (2_a): red brown, greenish red brown, 4-5 th grade. (2_b) red, red brown, 5 th grade. (2_c): orange red, brownish red, 45th grade.